Power-driven cutting blade and sharpening apparatus therefor



Dec. 16, 1952 C. A. CALLAHAN POWER-DRIVEN CUTTING BLADE AND SHARPENING APPARATUS THEREFOR Filed July 26, 1950 IN I 'EN TOR.

HTToR/VEYJ V Patented Dec. 16, 1952 OFFICE POWER-DRIVEN CUTTING BLADE AND SHARPENIN G APPARATUS THEREFOR Charles. A. Callahan, Philadelphia, Pa.

Application July 26; 1950, Serial No. 176,041

1 Claim.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention pertains to the art of sharpening power-driven cutting blades, and it comprises a structure that protects persons against danger of'injury while the cutting blade is being sharpened;

The invention embodies a housing enclosing the power-driven cutting blade, and sharpening apparatus for the cutting blade operable while the blade is in motion. The apparatus thus operates tosharpen the blade while the blade performs its. cutting operation. The novel structure enables the sharpening apparatus to be adjusted relative to the cutting blade to control the pressure applied for sharpening the blade, enabling these adjusting operations to be performed manually whilethe housing is in protective position. 'The adjustment may be made while the blade is engaged in performing the cutting operation for which it is intended.

The principlesoftheinvention, as-also a practical embodiment thereof, will be more clearly understood from the accompanying drawings to which attention is now directed.

In the drawings:

Fig. l'is front elevation of so much of a machine as embodies the present invention;

Fig. 2 is a fragmentary detail of the machine of 1;, with parts broken away for clearness of illustration, and

Fig. 3 is. a owes-sectional. elevation, taken online. 3-3 of Fig.2.

The invention is disclosed in the form of its practical application in a. machine for cutting b i The fabric-cutting machine of Fig... LcQmprises.

The cutting blade [5, is of the endless-band variety, which is sharp along its edge that is directed towards the observer in Fig. 1. The endless band I5 travels over the idler wheel's Hi and I! in the direction of the arrow in Fig. 1. and downwardly from the pulley I6 through'the table II, which is slottedto form a passage for the blade. The endless band I5 is driven in the direction of the arrow by any suitable and well-knownmechan-ism, which is not shown, the driving mechanism being unnecessary for understanding the present invention.

In the machine of the disclosed construction, the cutting blade I5 is sharpened continuously, and sharpening apparatus 20 is provided for the purpose. Sharpening apparatus 20 operates to keep the cutting blade l5 constantly inconditi'on for efiicient cutting, and also the cutting characteristics of the blade are maintained uniform.

Sharpening apparatus 20 comprises the set of grinding wheels 2| and 22, which are mounted to bear against and roll along the cutting edge of blade |'5'at its path of travel frompulley H to pulley l6. Wheels 2| and 22 press opposed to to each other on respective opposite sides of the blade I5.

Mounting of each of the wheels 21 and 22 is adjustable to vary the magnitude of pressure underwhichit bears against the blade I5, an object being to abrade the cutting edge of blade t5 only so much as is needed to'mai'ntain efficient and uniform cutting properties. Accordingly, the wheel 2 is carried. by the movable bracket 23', and wheel 22 is. similarly carried by movable: bracket 24, the brackets 23 and 24 each comprising a ,bellcrank lever respectively pivoted at 25' and 26. Spring 2,! actuates' bracket 23' to press the. wheel 2| upwardly against the lower side of the blade l5, and sprin 28 actuates racket 1 2 e he wheel 22 o wardlyagainst the upper side of the blade I5. The grinding wheels 2| and 22 are preferably not positioned directly opposite each other, but instead the wheel-22 is'positioned at a point somewhat i'urther al'ongf'rom wheel 2| in'tlre path of travel of the blade I5. Adjustment member 29 operates opposed to spring 21. tocontrol the'pressure of the wheel; 2| against the blade .li and similarly the adjustment member '30operates opposed to the spring 28 to control the pressure of wheel 22 against the opposite side of the blade.

Movable brackets or levers 23 and 24 are carried by the base plate 33, which is secured to the upright pane1 34 of the machine by means of bolts 35, for example. Base plate 33 includes the lugs 36 and 31, and each of the adjustment members 29 and 30 is in the form of a bolt that is threaded through its respective lug 36 and 31 and is held thereby directed towards its respective companion bracket 23 and 24, traverse of each bolt 29 and 30 being in a direction opposed to its respective spring 21 or 28. Each of the adjusting members 29 and 30 is provided with a knob 3|, and 32 respectively, which serves as a handle for making adjustments.

The endless cutting blade is completely housed, and this prevents injury to a person near the machine in the event that the blade breaks while it is travelling in operation of the machine. The housing is positioned where it also encloses the sharpening apparatus 20, which is a critical position where pressure is applied that may break the blade |5.

The housing comprises a front panel 49 spaced forwardly of the panel 34 as a back panel, panel 40 being in front of the blade l5 and the sharpening apparatus 2|} and panel 34 being behind. Along the top edge 4| of panel 4|), the side edges 42 and 43, and the bottom edges 43, there are bordering panels which close the space between the front and back panels 40 and 35 that contains the sharpening apparatus 29, the table II completing the closure. The travelling blade it is thus completely closed, particularly at the sharpening apparatus 20 where danger of its breaking is greatest, and the operator is thus completely protected from injury during operation of the machine and while the blade H3 is being sharpened.

The panels at 45, 42, 43 and id are attached peripherally to the front panel 43 to constitute a unitary structure therewith which is mounted to be swung towards and away from back panel 34 on the hinge 45 at the top. The handle 43 is attached to the housing of panel 48 to facilitate the housing being opened in the manner described.

The housing of panel 40 should be in protective closed position, not only while the sharpening apparatus 23 is operating, but also while it is being adjusted. This is particularly important because the adjusting mechanism which comprises springs 21, 28 and companion adjustment members 29, 30 operates to vary the pressure of grinding wheels 2| and 22 against the blade l5,

and the danger of the blade l5 breaking is increased thereby during the adjusting operation.

The front panel 43 is provided with the apertures 50 and 5| respectively proximate to the adjusting members 29 and 33. Apertures 5B and 5| serve as hand holes that permit access to the handles 3| and 32 of the respective adjusting members 29 and 30. Partitions 52 and 53 enclose the spaces inside respective apertures 55 and 5| that are occupied by respective knobs 3| and 32 and the hand of the operator when adjustment is being made, and they are thus positioned between the hand of the operator and the blade l5. The blade |5 is thus confined to prevent it i rearwardly of front panel 40 into engagement with the back panel 34. Slot 54 of partition 52 is an aperture in the housing only large enough to accommodate adjustment member 29, and slot 55 of partition 53 is similarly an aperture in the housing only large enough to accommodate adjustment member 30. Members 29 and 33 extend away from their respective lugs 36 and 3'! through respective slots 54 and 55 and handles 3| and 32 are thereby positioned inside their respective partitions 52 and 53 and exteriorly of the housing of front panel 40. v

The front panel is provided with an area 51 of transparent material which serves as a window through which the operator is able to observe his adjustment of wheels 2| and 22 with reference to the blade Hi.

When a blade |5 becomes broken, or needs to to be replaced or repaired, handle 46 is lifted to swing the front panel ill on the hinge and raise it out of the way. The front panel 40 is lifted out of the way in the same manner when grinding wheels 2| and 22 are replaced or removed for repair, as also for any other replacement or repair in the housing while the machine is not in operation. But whenever the machine is in operation and the cutting blade |5 is in motion, the panel 49 is lowered into protective position.

The panel is in protective position while either of the grinding wheels 2| and 22 is being adjusted to bear against the cutting edge of blade |5 with the required degree of pressure for the desired amount of abrasion. The operator inserts his hand into the space confined by the partition 52 to rotate the handle 3| manually for adjusting the wheel 2|, and in a like manner he inserts his hand into the space confined by the partition 53 to rotate the handle 32 manually for adjusting the wheel 22. The operator observes the correctness of the adjustment he is making through window 57. The adjustments are thus made safely while the blade [5 is travelling in operation. These adjustments may be made with complete safety while the machine is operating to cut fabric l2, which enables the operator to observe the effectiveness of the adjustment by observing the effect on the fabric being cut.

The accompanying disclosure is one practical application of the invention, which is susceptible of a number of modifications within the scope thereof. The scope of the invention is determined by the accompanying claim, to which attention is now directed.

I claim:

In a machine comprising a power-driven cutting blade apparatus to sharpen the blade, the sharpening apparatus comprising a sharpening tool and mechanism for adjusting its position relative to the blade, a housing comprising a front panel and a back panel respectively in front of and behind the sharpening apparatus and the cutting blade and comprising bordering side walls 0 extending rearwardly from the front panel to the back panel to enclose the sharpening apparatus and cutting blade, an adjusting member comprising a handle at its end for manually operating the adjusting mechanism and extending alongside and between the panels behind the front panel, a hand opening through the front panel opposite the handle of the adjusting memher and a partition peripherally of the hand opening and extending rearwardly from the front panel to the back panel into position around the 6 handle whereby the sharpening apparatus is ad- Number Name Date justable with the housing in protective position. 1,263,414 Hopkinson et a1. Apr. 23, 1918 CHARLES A. CALLAHAN. 1,511,788 Vaughan Oct. 14, 1924 1,772,705 Campbell Aug. 12, 1930 REFERENCES CITED 5 1,797,261 Hallam Mar. 24, 1931 The following references are of record in the 1,977,385 H0165 Oct- 16, 1934 file of this patent: fitricskfuss et a1. 3Iu1y ac on an.

UNITED STATES PATENTSD t 2,324,380 Frei July 3, 1943 Number Name a e 10 222,732 Plass Dec, 16, 1879 FOREIGN PATENTS 679,056 Lewis July 23, 1901 Number Country Date 720,227 Cormany Feb. 10, 1903 .282 Great Britain July 22, 1915 860,530 Cormany July 16, 1907 18,075 Great Britain DEC. 11, 1888 1,060,916 Luschka. Ma 6, 1913 15 2 4 Great Britain Dec. 6, 1894 1,160,946 Nangle Nov. 16, 1915 08 Germany 2 Oct. 31, 1938 1,255,040 Ousley Jan. 29, 1918 963,860 France May 10, 1950 

